1. Field of the Invention
The present invention relates to mobile terminals, such as cellular phones, PDAs (Personal Digital Assistants), HHPs (Handheld Phones), etc. More particularly, the present invention relates to a mobile terminal, which comprises a pair of sub-housings slidably movable on a main housing, and a sliding module of the mobile terminal and a method of sliding the sub-housings thereof.
2. Description of the Related Art
In general, the term “mobile terminal” means an electronic apparatus, which allows a user to perform wireless communication with others in a handheld state. Recently, mobile terminals have been designed to achieve miniaturization, slimness, and lighter weight to increase portability. Additionally, mobile terminals have been increasingly developed to support multimedia applications, which can provide various functions. Particularly, the mobile terminals have been both miniaturized and reduced in weight, as well as used for multi-function and multi-purpose applications. For example, the mobile terminals have been adapted to be appropriate for a variety of multimedia environments or Internet environments. Regardless of users' sex or age, mobile terminals are now used worldwide, and are viewed as a necessity of life, to be carried at all times.
Conventional mobile terminals can be classified into various types according to appearance. For instance, the mobile terminals can be classified into a bar-type terminal, a flip-type terminal, or a folder-type terminal according to their appearances. The bar-type terminal means a terminal having a bar-shaped single housing, the flip-type terminal means a terminal having a flip member rotatably coupled to the bar-shaped housing by a hinge member, and the folder-type terminal means a terminal having a folder rotatably coupled to the bar-shaped housing by a hinge member.
In addition to this classification, the conventional mobile terminals can be classified into a neck wearable type terminal and a wrist wearable type terminal according to how the terminal is worn, and can be classified into a rotational type terminal and a sliding type terminal according to the opening and closing method thereof. These mobile terminals, variously classified as mentioned above, can be easily understood by those skilled in the art of the present invention.
Meanwhile, in recent years, the mobile terminals have been developed to have a structure that allows high-speed data communication, as well as voice communication. That is, according to the increasing demands of users, the mobile terminals will be adapted to supply various services employing wireless communication technology that transmits data at high speed.
However, the conventional mobile terminal is provided with a restricted input means, for example, a keypad. Thus, when sending electronic mail or chatting, which requires the input of a great amount of data, characters must be input by means of keys, restricted in number on the keypad, thereby frequently causing inconvenience due to the need to press one key several times according to a shape of a letter. Furthermore, since the number of keys constituting the keypad is restricted, there is a problem in that users can only play games using the limited number of keys.